With the continuous development of the display technology, the organic light-emitting diode (OLED) display device as a new panel display device will inevitably become the developing trend of the display device of next generation by virtue of its advantages of light volume, high contrast, high color gamut, low power consumption, and flexible display.
According to the difference in the driving mode, the OLED display device can be divided into: Passive Matrix Organic Light Emission Display (PMOLED) and Active Matrix Organic Light Emission Display (AMOLED). Relative to the PMOLED, the AMOLED has a higher response speed, and can meet the requirements of display devices in various sizes, hence, many enterprises pay more attention to the AMOLED.
In the prior art, according to the difference in the forming material of the thin film transistor (TFT) active layer, the AMOLED array substrate mainly includes a low temperature polysilicon array substrate and an oxide array substrate. For the low temperature polysilicon array substrate, when the low temperature polysilicon after crystallization is in grain state, there is certain gap between the grains, such that the threshold voltage of the TFT can easily drift, and the uniformity of the array substrate is relatively bad. In order to improve uniformity of the array substrate, the drift of the threshold voltage may be eliminated by arranging a plurality of TFTs. However, the increase of the TFT amount will in turn result in slow-down of the switching speed of the pixel, and result in complexity of the fabricating process of the array substrate. Moreover, the low temperature polysilicon requires a relatively high temperature in crystallization, which will also increase complexity of the fabricating process. For the oxide array substrate, since the current carrier mobility in the electrified oxide is relatively low, it cannot fulfill the characteristic of the OLED as a current device that needs support of a relatively high current carrier mobility better, thereby resulting in a relatively low switching speed of the TFT.